Threshold


The threshold binary sensor platform observes the state of another sensor. If the value is below (lower) or higher (upper) than the given threshold then state of the threshold sensor is changed. It support also a range if lower and upper are given.

If the sensor is configured with no hysteresis and the sensor value is equal to the threshold, the sensor is turned off since it is not lower or upper with respect to the threshold.

It’s an alternative to the template binary sensor’s value_template: to get the abnormal/too high/too low states.

{{ states('sensor.furnace') > 2.5 }}

Configuration

To enable the threshold sensor, add the following lines to your configuration.yaml:

# Example configuration.yaml entry
binary_sensor:
  - platform: threshold
    entity_id: sensor.random
    lower: 20

Configuration Variables

entity_id string Required

The entity to monitor. Only sensors are supported.

lower float (Optional)

The lower threshold which the observed value is compared against.

upper float (Optional)

The upper threshold which the observed value is compared against.

hysteresis float (Optional, default: 0.0)

The distance the observed value must be from the threshold before the state is changed.

name string (Optional, default: Threshold)

Name of the sensor to use in the frontend.

Examples

Is the temperature rising or falling

The hysteresis parameter can be used in this use-case to avoid frequent state changes around the maximum or the minimum of a temperature curve. We also have to utilize the derivative sensor for this use-case:

sensor:  
  - platform: derivative # will be positive for rising temperatures and negative for falling temperatures
    source: sensor.temperature
    unit_time: min
    name: temperature derivative
    time_window: 00:05:00
binary_sensor:
  - platform: threshold # will switch state not at 0°C/min but 0.1°C/min or -0.1°C/min depending on the current state of the sensor, respectively
    entity_id: sensor.temperature_derivative
    upper: 0
    hysteresis: 0.1 # sensor 
    name: temperature rising